The New York Times, November 21, 1997, p. A17:
Germ Weapons: Deadly, but Hard to Use
By Nicholas Wade [Science writer for The New York Times]
The horror of germ weapons is easier to describe, experts say, than to translate into
practice. How far Iraq's scientists have succeeded in building a practical arsenal of
biological weapons remains unclear despite five years of investigation by U.N.
inspectors.
Biological weapons have several properties that might be attractive to a country like Iraq. If
properly deployed, they could cause civilian casualties in numbers comparable to those of a
nuclear weapon. Unlike nuclear weapons, they are easy to manufacture and conceal.
Just a flask of culture can produce pounds of anthrax bacteria in four days. One gram --
about 0.04 ounces, or the weight of two paper clips -- contains enough doses to kill 10
million people.
Botulinum toxin, another agent prepared by Iraq, is one of the most poisonous substances
known. The lethal dose is one billionth of a gram per kilogram, meaning that breathing in 70
billionths of a gram would kill a person weighing 70 kilograms or 154 pounds. The toxin is
fatal within three days to 80 percent of those exposed.
But to serve as weapons, both anthrax and botulinum toxin need to be inhaled. That
requires gently dispersing them as a mist at ground level, a difficult task in war conditions.
A crop-dusting plane, the ideal delivery vehicle, would have little chance of reaching its
target, although Iraq was experimenting with a mist-dispensing helicopter.
The agents can be dispersed from bombs or missile warheads, both of which Iraq was
working on. But the technical problems are severe, experts say. The heat of the dispersing
explosion can easily cook the agents into inactivity or harmless clumps.
Anthrax, however, can be formed into hardy spores that can spread through the wind.
U.N. inspectors have established that Iraq's biological weapons were being developed in a
20-year program. The technical quality of the program is hard to gauge. Some experts have
said that Iraq's work on aflatoxin, a curious choice for a biological weapon since it is not
highly potent, suggests its scientists did not know what they were doing. Others believe the
Iraqis may have discovered something new.
"Some might say they made a mistake," said Dr. Graham Pearson, former director-general
of the British chemical and biological defense establishment, adding that he did not share
the view because of Iraq's known technical sophistication in other areas, such as making
chemical weapons with ingredients designed to mix in flight.
"I haven't seen a clear explanation as to why Iraq was interested in aflatoxin, and that is
why it is so important that the U.N. Special Commission does get to the bottom of the Iraqi
program," Pearson said.
The likely effect of biological agents remains to some extent a matter of conjecture because
they have seldom been used in warfare. They depend primarily on wind for their dispersal,
a factor that is hard to predict or control. And troops, once warned, can easily protect
themselves with the right equipment.
"Anthrax is a terror agent, not a battlefield agent," said Dr. Norton Zinder, a biologist at
Rockefeller University who has advised the U.S. Army. "The psychology of biological
weapons is more potent than the weapons are," he said.
Still, the terror has a hard basis in fact. A warning of what a real anthrax attack might do to
a city emerged from an accident in 1979 at a Soviet biological warfare plant in a residential
neighborhood of Sverdlovsk, now known as Ekaterinburg, some 870 miles east of Moscow.
Dr. Matthew Meselson, a Harvard biologist and expert on biological weapons, was recently
allowed to visit the city and to reconstruct the likely sequence of events.
No more than a gram of anthrax spores, and maybe as little as a few thousandths of a gram,
escaped from the plant, according to his calculations, yet that was enough to kill 96 people
who were downwind of the release. The contaminated plume swept beyond the city and
killed sheep that were grazing 30 miles away. In one location, a nearby ceramics factory,
the spores that wafted in through doors and windows killed 2 percent of the people inside.
Someone who efficiently distributed anthrax at a low altitude over a city could kill millions,
Pearson said. A recent report by the Office of Technology Assessment described agents like
anthrax as "true weapons of mass destruction with a potential for lethal mayhem that can
exceed that of nuclear weapons."
Anthrax is not contagious but possesses another feature that adds to its fearsomeness: its
spores, like radioactivity, can persist for decades. Speculation that large areas could be
rendered permanently uninhabitable by anthrax have been bolstered by reports of events on
Gruinard Island, a speck of land off the north-west coast of Scotland.
During the World War II, British scientists exploded anthrax bombs on the island to prove
their feasibility for use against German cities. The island was kept off limits for decades
since the spores persisted in the soil. In 1990, the Ministry of Defense decided to
decontaminate the island and return it to its owners. A mixture of sea water and diluted
formaldehyde was used to kill the spores.
There is some debate as to how dangerous the island was during its period of quarantine.
Though anthrax was present, the spores were probably not particularly deadly unless
disturbed from the soil. A territory might be contaminated with anthrax but still be habitable,
although with some risk. "While the actual hazard after an attack might be slight, there
would be living spores on the surface and that would be of public concern," Pearson said.
Anthrax is probably the best candidate for a biological weapon, but it is always possible that
Iraq has found other agents. One of the deadliest, now that people are no longer vaccinated
against it, is the smallpox virus, which causes devastating epidemics in unprotected
populations.
"The agent that worries me the most in biological terms is smallpox," Zinder of Rockefeller
University said, but the U.N. inspectors have found no evidence that it was among the
agents of interest to Iraq.
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